Bushing for rotary tables



lune 13, 1933. I I E, LYNN Er AL 1,914,210

UsHING FOR ROTARY'-TABLES 2 Sheets-Sheet 1 Original Filed May 14, 1929 June 13, 1933.

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Original Filed Ma H. E. LYNN Er AL BUSHIN'G FOR ROTARY TABLES 2 Sheets-Sheet 2 Patented lune 13, 1933 UNITED STATES PATENT OFFICE HARRY E. LYNN, 0F MAYWOOD, AND FRED LAMBERT, JR., 0F EAGLE ROCK, CALIFOR- NIA, ASSIGNORS 0F TWENTY-SEVEN PER CENT T0 WILLIAM A. SMITH, EIGHTEEN' AND ONE-FOURTH PER CENT T0 WILLIAM A. VOCK, AND EIGHTEEN AND ONE- FOURTH .'PER CENT TO FOX M. IBOSWELL, ALL 0F LONG BEACH, CALIFORNIA BUSHING- FOR ROTARY TABLES Application filed May 14, 1929, Serial No. 362,990. Renewed December 13, 1932.

This invention has to do with a bushing for a rotary table and it is a general object of the invention to providean improved, practical, and economical bushing for use in the table of a rotary well drilling outfit.

In the drilling of wells with the rotary method it is common to use what is known as a rotary unit, or table, to drive the drill string. In standard equipment a Kelly or drill stem is attached to the drill string' and is engaged by bushings carriedin the rotary table, the engagement being such as to allow the drill stem to be raised and lowered through the table while the driving engagement is' maintained between the table and drill stem. In practice considerable frictionv and wear occurs between the' drill stem and thebushings carried in the rotary table.

The present invention provides .an improved form of bushing construction for use in a rotary table, and/the invention has among its objects the provision of a bushing which materially reduces wear and friction, which operates effectively and smoothly, and which is economical and commercially practlcal.

It is a general object of the present invention to provide a bushing that will pass a drill stem with a minimum of friction and at the same time maintain an effective driving engagement with the drill stem. I

It is another object of the invention to provide a construction whereby drill stems of various sizes can be accommodated conveniently and at low costs.

It is a further object of the present invention to provide a device of' the character mentioned which is sturdy and durable. The device provided by the invention is such as to electively withstand the severe use that frequently comes upon the bushings of a rotary table, and it is of such nature as to operate with little wear or deterioration.

Another object of the invention'is to provide a device of the character described that is safe to operate. The invention provides a construction and arrangement which minimizes the danger of parts being broken or lost, in a manner to fall into the well bore or otherwise cause trouble.

It is another object of the present invention to provide a construction for a device of the character mentioned which embodies a plurality ofrotatable members to engage the drill stem but is free of delicate locking devices or retaining means subject to failure or such as to cause trouble or delay in operatlon.

The-various objects and features of the invention will be best and more fully understood from the following detailed description of a typical form and application ofthe invention, throughout which description reference is had to the accompanying drawings, in which:

Fig. 1 is a detail sectional view illustrating a typical rotary unit with a Kelly or drill v stem arranged through it and with a bushing device provided by this invention forming a driving connection between the unit and drill stem. Fig. 2 is a plan view of the parts shown in Fig.v1. Fig. 3 is an enlarged side view of the construction provided by this invention showing certain parts broken away to be in section. Fig. 4 is a plan view of the device shown in Fig. 3 with parts broken away to show in section. Fig. 5 is a top or plan view of onev of the cages of the construction provided by this invention. Fig. 6 is a vertical sectlonal vlew of a cage, being a view taken as indicated by line 6-6 on Fig. 5, and Fig.

7 is a side view of a cage, being a view taken as indicated by line 7 -7 on Fig. 6.

The device provided by this invention is intended primarily for use in connection with this standard or common form of rotary drilling equipment, it being understood, however, that various modifications and variations may be made in the invention to accommodate it to various vtypes of equipment. To facilitate an understanding of the invention, we have illustrated it as applied to a standard form of rotary unit 10 and drill stem 11. The rotary unit 10 has in addition to the-various parts common to devices of this character, la table 12 with a central vertical opening 13 carrying a master bushing 14. The master bushing is held in the table against rotation and has a central vertical opening passingthe drill stem 11 and adapted to recelve a bushing for establishing a driving connection between the master bushing 1d and the drill stem 11. The opening in the master bushing has a tapered or downwardly convergent portion which is round in cross section and has a straight polygonal portion 16 immediately above the tapered portion 15. ln practice the polygonal ortion of the bushing opening is su stantially square in cross section.

rlhe device provided by our invention is adapted to be carried in the master bushing 1d and is designed to engage the drill stem 11 to establish a driving connection between the master bushing 14 or table 12 and the drill stem 11. rllhe 'device includes, generally,'a body 17 to be mounted in the rotary unit 10, a plurality of cages 18 to be carried in the body 17, means 19 for retaining the cages in the body, and rollers 2() carried in the cages to engage the drill stem 11. lll/'hen the device is to be used in connection with standard equipment, such as we have referred to and such as is illustrated in Figs. 1 and 2 of the drawings the body 17 is designed to lit the o ening ofthe master bushing 1d. 'lhe body 1 portion 21 to t the tapered opening 15 of the master bushing and is provided with a polygonal portion 22 immediately above the portion 21 to t the portion 16 of the opening of the master bushing 1a. ln the particular design of the invention illustrated, the body 17 .extends or projects a substantial distance above the portion 22, giving the device considerable length and making it possible to obtain roller carrying cages of substantial length.

rlhe body 1,7 has a central vertical opening extending through it, said opening being designed and proportioned to accommodate the cages 18. ln the form of the invention i1- lustrated the cages 18 are adapted to be arranged in the body 17 through its upper end r and the cage receiving portion of the body opening is shaped to edectively support the cagesin operating position. ln `the case of a device designed to accommodate a standard form of drill stem, such drill stem being substantially square in cross section, the device is provided with four cages 18, and the cage receiving portion of the body opening is formed with four walls 23 which support the cages.

A rest or stop 2d is provided in the body 17 near its lower end to limit downward movement of the cages inthe body. The stop 2d may be in the form of a dange projecting inwardly in the body opening to extend under the cages, as clearly shown in Fig. 3. lin practice considerable strain mayat times come upon the stop 2d, and therefore it is desirable to reinforce it by means of braces or ribs 25.

'.lhe cages 18, which are arranged in thev body 17 and which car the rollers 20, are adapted to be arrange in the body 17 is provided with a tapered lower noreste through its upper end, and when in place fare supported by the walls 23 of the body and stop 24:. v

Each cage 18 is preferably in the form of a rectangular frame adapted to fit against one of the side Walls 23 ofthe body opening. The frame formation of the cage may include spaced vertical sides 30, a top 31 joining the. upper ends of the sides, and a bottom 32 joining the lower ends of the sides. lln accordance with the preferred form of the invention, the cages are designed to mesh or cooperate so that they hold each other in place, that is, in operating position 1n engagement with the walls 23 of the body opening. ln the form of the invention shown, one side 30 of each frame is provided with a vertical recess 33 in one corner to receive thecorner of the adjoining frame. The manner in which the frames are recessed and it together is clearly illustrated in Fig. d of the drawings. With this arrangement the frames hold one another against falling inwardly.

'lhe rollers 20 are mounted horizontally in the cages 18 so that they project inwardly from the cages in al manner to engage the drill'stem 11. 'lhe several rollers carried by each cage 18 are located in vertical alignment, that is, one above the other., in the manner clearly illustrated in Figs. 3, 6 and7 of the drawings.

, The rollers 20 are suciently long and are .l so located in the cages 18 as to have edectlve bearing or driving engagement with the drill stem 11. ln this connection it may be noted that the cages 18 and rollers 20 may be designed so that the rollers engage the drill stem 11 in a manner such as is illustrated in lFi d of the drawings.

lin accordance with the preferred form of the invention, the rollers are mounted in the cages 18 by means of pins 40 which project through the rollers and have end portions projecting into openings 41 provided in the sides 3l of the cages 18. ln practice the rollers 20 are made of such length as to extend substantially the entire distance between the reo sides 30 of -the cages and are spaced apart ing devices or other parts subject to failure or requiring attention.

lin assembling the construction the rollers are placed between the sides of the cage and the pins forced or pressed through the rollers until their end portions are in proper position in the openings 41. For the'purpose of lubrication vertical openings l5 may be formed in the sides 30 of the cages 18 in a manner to communicate with the pin support openings 41, as clearly shown in Figs. 6 and 7 of the drawings. Suitable lubricant may be supplied to the openings 45 through fittings 46 applied to the ends of the openings as shown in Fig. 6. With this arran ement, an occasional application of a suita le lubricant keeps the unit in perfect working condition.

The locking or retaining means 19, pro` vided for holding the cages 18 in the body 17, is in the nature of a clamp device applied to the upper end portion of the body 17 to engage and hold the cages 18. In the preferred form of the invention the locking means includes a ring 50 screw threaded to the upper end portion of the body 17 and having a flange portion 51 overhanging or projecting inwardly over the upper ends of the cages. This is a simple, effective construction for retaining the cages in the body. It is to be noted that this construction permits of the cages being removed from the body quickly and without the aid of special tools or equipment. The clamping device or ring is preferably provided with a lock or setting means to prevent it from working loose. In the construction illustrated we provide a screw threaded opening 81 in the liange 51 and arrange a locking pin 80 in the opening 8l to project into a socket in the upper end of the body. This construction is clearly illustrated in Fig. 3 of the drawings.

In using the construction provided by this invention, it is applied to the rotary unit in the manner illustrated in Figs. 1 and 2 of the drawings and during operation of the equipment the table is rotated so that driving strain is communicated through the device to the drill stem 11. The numerous rol- 1ers carried in the cages provide ample bearing on the drill stem so that the rotational strain is properly communicated between the unit 10 and drill stem 11. The rollers 20, being mounted on horizontal axes, allow free movement of the drill stem vertically through the unit at all times, that is, when the table is being rotated or when it is standing still. The 'free operation of the drill stem through the device operates. to materially improve the action of the drilling equipment as it prevents binding and causes the equipment to operate smoothly. When it is desired to use a drill stem 11 of a different size, it is unnecessary to replace the entire device provided by this invention by one of a different size. With the present invention it is merely necessary to release the retaining means 19 by releasing the pin 80 and disengaging the ring 50 from the body 17, remove the cages 18, and replace them with cages of different proportions, that is, with cages proportioned to fit the drill stem 11 to be used. Thus it will be apparent that the present invention provides a construction whereby a single device, equipped with sets of cages of different sizes, may accommote drill stems of different sizes. This feature of the invention is very important as it makes it unnecessary for an operator to purchase complete units or devices for each size drill pipe that he may desire to operate; further, the removable cage construction that we have provided makes it possible to easily, quickly, and economically replace the wearing parts, that is, those parts subject to wear or injury.

Having described only a typical, preferred form of the invention, we do not wish to limit ourselves to the specific details set forth, but wish to reserve to ourselves any changes or variations that may appear to those skilled in the art or fall within the scope of the following claims.

Having described our invention, we claim:

1. In combination, a rotary table, a master bushing carried by the rotary table and having an opening, a drive bushing body carried in said opening and having a vertical opening extending through it adapted to pass a drill stem, a plurality of cages in the body, means for removably retaining the cages in the body, and rollers carried in the cages for engaging a drill stem, the said means including a member screw threaded on the body and extending over the body opening to engage the cages, and a screw for locking the member in position.

2. In combination, a rotary table, a master bushing carried by the rotary table and having an opening, a drive bushing body carried in said opening and having a vertical opening extending through it adapted to pass a drill stem, a plurality of cages in the body, means for removably retaining the cages in the body, and rollers carried in the cages for engaging a drill stem, the said means including a member screw threaded to the body.

3. Tn combination, a rotary table, a master bushing carried by the rotary table and having an opening, a drive bushing body carried in said opening and havingA a vertical opening extending through it adapted to pass a drill stem, a plurality of cages in the body, means for removably. retaining the cages in the body, and rollers carried in thev cages for engaging a drill stem, the said means including a member screw threaded to the body, and means for locking said member in operating position. Y

4*. ln combination, a rotary table, a master bushing carried in the table, a body carried in an opening in the master bushing and having an opening for passing a drill stem, and a plurality of roller carrying cages arranged in the body opening, each cage having a recess to receive a portion of an adjoining cage so that the cages are held in position to pass a polygonal drill stem, and means for retain- Lolli-,21e

ing the cages in the body, said means including a ring sereT threaded on the upper en of the body, and a flange on the ring eX- tending over the body opening to engage the cages.

5. In combination, a rotary table, a master bushing Carried in the table, a body carried in an opening in the master bushing and having an opening for passing a drill stein,

l@ a plurality of cages arranged in the opening in the body, rollers Carried by the cagesv to engage a drill stem, and means for retaining the Cages in the body including a ring screw threaded to the body.

l ln Witness that We claim the foregoing We have hereunto subscribed our names this 6th day of May, 1929.

HARRY E. LYNN.

FRED LAMBERT, JR. 

